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Ground state of a partially melted Wigner molecule

Zoltan Adam Nemeth·Jean-Louis Pichard
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Abstract

We consider three spinless fermions free to move on 2d square lattice with periodic boundary conditions and interacting via a U/r Coulomb repulsion. When the Coulomb energy to kinetic energy ratio r_s is large, a rigid Wigner molecule is formed. As r_s decreases, we show that melting proceeds via an intermediate regime where a floppy two particle molecule coexists with a partially delocalized particle. A simple ansatz is given to describe the ground state of this mesoscopic solid-liquid regime.

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Zoltan Adam Nemeth, Jean-Louis Pichard. 2002-03-22. Ground state of a partially melted Wigner molecule. https://doi.org/10.1209/epl%2Fi2002-00412-2

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